Nearly 100,000 acres have been destroyed by wildfires in recent weeks, and thousands have been forced from their homes.
Several of this year’s major wildfires have burned in unforested areas.
“Every year, as the fire’s (sic) rage & California burns, it is the same thing – and then he comes to the Federal Government for $$$ help. No more. Get your act together Governor,” Mr Trump wrote on Twitter.
Drier, warmer conditions lead to vegetation drying out and becoming more flammable.
President Trump made a similar threat to cut federal aid in 2018, when the most deadly fire in California’s history killed 86 people.
In California, 57% of forested areas are managed by federal agencies such as the US Forest Service, the Bureau of Land Management and the National Park Service.
In 2018, the state requested $72 million (£55.6 million) in reimbursements from the US Forest Service, with $9 million (£7 million) of that money withheld, the Los Angeles Times reports.
What’s happening with the fires?
The fire, which broke out on Thursday, has burned more than 9,400 acres, the Ventura County Fire Department said on Sunday.
The largest blaze, the Kincade Fire in Sonoma County, was 76% contained on Sunday after burning nearly 80,000 acres since it started on 23 October, officials said.
All evacuation orders were lifted on Saturday.